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Module 11: Collections Framework Deep Dive

Lesson focus

Mini-Project: Contact Management System

Manage contacts using maps, sets for deduplication, and comparators for sorted views.

Store contacts keyed by ID in HashMap, maintain a TreeSet for alphabetical listing.

Allow lookup by tags using Map<String, Set<Contact>>.

Persist data to JSON/CSV and import/export while handling duplicates gracefully.

Lesson quiz

Which structure ensures contacts remain sorted by name?

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